ACHATINA.— Plate I. 
Rotssy, Buffon de Sonnini, Hist. Moll. p. 354. 
Bulla ackatina, Linnaeus. 
Buccinum achatinum, Muller. 
Buccinum variegatum , Pabius Columna. 
Bulimus achatimts, Bruguiere. 
Cochlitoma achatina, Ferussac. 
Achatina perdix, Lamarck. 
Iiab. Sierra Leone &e., West Africa (in tbe woods). 
This fine large species exists in great abundance in the 
woods of West Africa, with little variation except that the 
striped painting is sometimes absent, as in PI. V. 
Species 4. (Mus. Cuming.) 
Achatina bicolor. Achat, testa subelongato-tnrritd, 
anfractihus septeni , subirregulariter striatis, ad suturas 
indistinct plicato-cremlatis, columella, arcuata et con- 
torta , fortiter truncatd, aperture, pared ; intense pur- 
pureo-nigrd , apicem versus castaned, columella camlet- 
cente-albd. 
The two-coloured Achatina. Shell somewhat elon- 
gately turreted, whorls seven in number, rather 
irregularly striated, indistinctly plicately crenulated 
at the sutures, columella arched and twisted, strongly 
truncated, aperture small ; intense purple-black, 
chesnut towards the apex, columella bluish-white. 
Jay, Cat. Mus. p. 119. 
Achaiinella bicolor, Pfeiffer. 
Achatina adusta, Gould (fide Pfeiffer). 
Sab. Sandwich Islands. 
This shell has not the generic character of Achatinella, 
the species of which are more or less polished, and dis- 
tinguished by a peculiar screw-like twist of the columella. 
Species 5. (Mus. Cuming.) 
Achatina cochlea. Achat, testa elongato-turrita, an- 
fractibus octo, spiraliter costatis, supemc depressis, 
infra convexo-planis, basi subangulatis, columella pro- 
funde arcuata et contorta ; ustulato-castanea, zonula 
alba infra suturas. 
The screw Achatina. Shell elongately turreted, 
whorls eight in number, spirally ribbed, depressed 
round the upper part, convexly flattened beneath, 
slightly angled at the base, columella deeply arched 
and twisted ; burnt chesnut colour, with a narrow 
white zone beneath the sutures. 
Hab. Peru. 
This species is chiefly remarkable on account of its 
elongated form and spiral ribbed structure, having much 
the aspect of a Turritella. 
